- Electrochemical Synthesis of Allylic Amines from Terminal Alkenes and Secondary Amines
-
Allylic amines are valuable synthetic targets en route to diverse biologically active amine products. Current allylic C-H amination strategies remain limited with respect to the viable N-substituents. Herein, we disclose a new electrochemical process to p
- Targos, Karina,Wang, Diana J.,Wickens, Zachary K.
-
supporting information
p. 21503 - 21510
(2022/01/03)
-
- GINGEROL DERIVATIVE HAVING INHIBITORY ACTIVITY AGAINST BIOFILM FORMATION AND PHARMACEUTICAL COMPOSITION COMPRISING SAME AS EFFECTIVE INGREDIENT FOR PREVENTING OR TREATING BIOFILM-CAUSED INFECTION SYMPTOM
-
The present invention relates to a gingerol derivative having inhibitory activity against biofilm formation and a pharmaceutical composition for preventing or treating infections caused by biofilms including the gingerol derivative as an active ingredient. The gingerol derivative of the present invention exhibits significantly improved binding affinity for LasR and inhibitory activity against biofilm formation. Therefore, the gingerol derivative of the present invention can act on various membrane surfaces where biofilms tend to form and can effectively inhibit the formation of the corresponding biofilms. In addition, the use of the pharmaceutical composition according to the present invention can fundamentally prevent or treat a variety of infections caused by biofilms due to the presence of the gingerol derivative in the pharmaceutical composition.
- -
-
Paragraph 0032; 0117-0118
(2020/09/22)
-
- Copper-Catalyzed Regioselective Borocarbonylative Coupling of Unactivated Alkenes with Alkyl Halides: Synthesis of β-Boryl Ketones
-
The borocarbonylative coupling of unactivated alkenes with alkyl halides remains a challenge. In this communication, a Cu-catalyzed borocarbonylative coupling of unactivated alkenes with alkyl halides for the synthesis of β-boryl ketones has been developed. A broad range of β-boryl ketone derivatives was prepared in moderate to excellent yields with complete regioselectivity.
- Wu, Fu-Peng,Yuan, Yang,Schünemann, Claas,Kamer, Paul C. J.,Wu, Xiao-Feng
-
supporting information
p. 10451 - 10455
(2020/05/08)
-
- Introduction of Cyclopropyl and Cyclobutyl Ring on Alkyl Iodides through Cobalt-Catalyzed Cross-Coupling
-
A cobalt-catalyzed cross-coupling between alkyl iodides and cyclopropyl, cyclobutyl, and alkenyl Grignard reagents is disclosed. The reaction allows the introduction of strained rings on a large panel of primary and secondary alkyl iodides. The catalytic system is simple and nonexpensive, and the reaction is general, chemoselective, and diastereoconvergent. The alkene resulting from the cross-coupling can be transformed to substituted cyclopropanes using a Simmons-Smith reaction. The formation of radical intermediates during the coupling is hypothesized.
- Andersen, Claire,Ferey, Vincent,Daumas, Marc,Bernardelli, Patrick,Guérinot, Amandine,Cossy, Janine
-
supporting information
p. 2285 - 2289
(2019/03/29)
-
- APOPTOSIS SIGNAL-REGULATING KINASE INHIBITORS AND USES THEREOF
-
Described herein are ASK1 inhibitors and pharmaceutical compositions comprising said compounds. The subject compounds and compositions are useful for the treatment of blood disease, autoimmune disorders, pulmonary disorders, hypertension, inflammatory diseases, fibrotic diseases, diabetes, diabetic nephropathy, renal diseases, respiratory diseases, cardiovascular diseases, acute lung injuries, acute or chronic liver diseases, and neurodegenerative diseases.
- -
-
Paragraph 00517
(2019/04/09)
-
- A convenient synthesis of the enantiomerically pure (S)-2,4-dihydroxybutyl-4-hydroxybenzoate using hydrolytic kinetic resolution
-
(S)-2,4-Dihydroxybutyl-4-hydroxybenzoate was prepared in an extremely simple and practical way with high enantiomeric excess (99% ee) using Jacobsen’s Hydrolytic Kinetic Resolution technique as a key step and source of chirality.
- More, Namita A.,Jadhao, Nitin L.,Garud, Dinesh R.,Gajbhiye, Jayant M.
-
supporting information
p. 2093 - 2098
(2018/07/15)
-
- Branch-Selective Addition of Unactivated Olefins into Imines and Aldehydes
-
Radical hydrofunctionalization occurs with ease using metal-hydride hydrogen atom transfer (MHAT) catalysis to couple alkenes and competent radicalophilic electrophiles. Traditional two-electron electrophiles have remained unreactive. Herein we report the reductive coupling of electronically unbiased olefins with imines and aldehydes. Iron catalysis allows addition of alkyl-substituted olefins into imines through the intermediacy of free radicals, whereas a combination of catalytic Co(Salt-Bu,t-Bu) and chromium salts enables a branch-selective coupling of olefins and aldehydes through the formation of a putative alkyl chromium intermediate.
- Matos, Jeishla L. M.,Vásquez-Céspedes, Suhelen,Gu, Jieyu,Oguma, Takuya,Shenvi, Ryan A.
-
supporting information
p. 16976 - 16981
(2019/01/04)
-
- Stereoselective synthesis of 1,3-disubstituted dihydroisoquinolines vial-phenylalanine-derived dihydroisoquinoline N-oxides
-
The preparation of chiral pool-derived nitrone 3 and its use in the protecting-group free, stereoselective synthesis of a range of 1,3-disubstituted tetrahydroisoquinolines is described. Grignard reagent additions to nitrone 3 yielded trans-1,3-disubstituted N-hydroxytetrahydroisoquinolines 6 with good levels of selectivity, while 1,3-dipolar cycloadditions to this nitrone provided access to 3-(2-hydroxyalkyl)isoquinolines 12 as single diastereomers.
- Flores-Ferrándiz, Jesús,Carter, Nicholas,González-Soria, Maria José,Wasinska, Malgorzata,Gill, Daniel,Maciá, Beatriz,Caprio, Vittorio
-
supporting information
p. 6961 - 6968
(2018/10/17)
-
- Auto-Tandem Catalysis with Frustrated Lewis Pairs for Reductive Etherification of Aldehydes and Ketones
-
Herein we report that a single frustrated Lewis pair (FLP) catalyst can promote the reductive etherification of aldehydes and ketones. The reaction does not require an exogenous acid catalyst, but the combined action of FLP on H2, R-OH or H2O generates the required Br?nsted acid in a reversible, “turn on” manner. The method is not only a complementary metal-free reductive etherification, but also a niche procedure for ethers that would be either synthetically inconvenient or even intractable to access by alternative synthetic protocols.
- Bakos, Mária,Gy?m?re, ádám,Domján, Attila,Soós, Tibor
-
supporting information
p. 5217 - 5221
(2017/04/27)
-
- Structure-Activity Relationships of 6- and 8-Gingerol Analogs as Anti-Biofilm Agents
-
Pseudomonas aeruginosa is a causative agent of chronic infections in immunocompromised patients. Disruption of quorum sensing circuits is an attractive strategy for treating diseases associated with P. aeruginosa infection. In this study, we designed and synthesized a series of gingerol analogs targeting LasR, a master regulator of quorum sensing networks in P. aeruginosa. Structure-activity relationship studies showed that a hydrogen-bonding interaction in the head section, stereochemistry and rotational rigidity in the middle section, and optimal alkyl chain length in the tail section are important factors for the enhancement of LasR-binding affinity and for the inhibition of biofilm formation. The most potent compound 41, an analog of (R)-8-gingerol with restricted rotation, showed stronger LasR-binding affinity and inhibition of biofilm formation than the known LasR antagonist (S)-6-gingerol. This new LasR antagonist can be used as an early lead compound for the development of anti-biofilm agents to treat P. aeruginosa infections.
- Choi, Hyunsuk,Ham, So-Young,Cha, Eunji,Shin, Yujin,Kim, Han-Shin,Bang, Jeong Kyu,Son, Sang-Hyun,Park, Hee-Deung,Byun, Youngjoo
-
p. 9821 - 9837
(2017/12/26)
-
- SILVESTROL ANTIBODY-DRUG CONJUGATES AND METHODS OF USE
-
The invention relates generally to a silvestrol molecule activated with a leaving group. The invention further relates generally to an antibody-drug conjugate comprising an antibody conjugated by a linker to one or more silvestrol drug moieties and methods of treatment.
- -
-
Page/Page column 93
(2018/01/15)
-
- Developing a Bench-Scale Green Diboration Reaction toward Industrial Application
-
We report a new methodology for the organocatalytic diboration reaction using inexpensive, sustainable, nontoxic, commercially available halogen salts. This is an educative manuscript for the transformation of laboratory scale reactions into a sustainable approach of appeal to industry.
- Farre, Albert,Briggs, Rachel,Pubill-Ulldemolins, Cristina,Bonet, Amadeu
-
supporting information
p. 4775 - 4782
(2017/10/27)
-
- Chemo- and regioselective reductive transposition of allylic alcohol derivatives via iridium or rhodium catalysis
-
We report highly chemo- and regioselective reductive transpositions of methyl carbonates to furnish olefin products with complementary regioselectivity to that of established Pd-catalysis. These Rh- and Ir-catalysed transformations proceed under mild conditions and enable selective deoxygenation in the presence of functional groups that are susceptible to reduction by metal hydrides.
- Lundgren, Rylan J.,Thomas, Bryce N.
-
supporting information
p. 958 - 961
(2016/01/20)
-
- 4-Isopropylchroman-3-ol derivatives
-
The present invention relates to a novel 4-isopropylchroman-3-ol compound, a pharmaceutical composition comprising the novel compound as an effective component, and to an intermediate compound useful for synthesizing the compound. When administered to a patient with a drug causing toxicity, the novel 4-isopropylchroman-3-ol compound exhibits efficacy of reducing toxicity of the drug by reducing antagonism regarding a T-type calcium channel and/or activity of cytochrome P450 isozyme.
- -
-
Paragraph 0212-0214
(2017/04/19)
-
- Regioselective dihydropyran formation from 4-iodo-2,6-disubstituted tetrahydropyran derivatives using In(OAc)3/LiI system as the promoter
-
The rapid and regioselective synthesis of a series of 2,6-disubstituted dihydropyranic building-blocks bearing an oxygenated side chain is described. The corresponding 4-iodo tetrahydropyran precursors, easily prepared by Prins cyclization, underwent regi
- Chalopin, Thibaut,Jebali, Khaoula,Gaulon-Nourry, Catherine,Dénès, Fabrice,Lebreton, Jacques,Mathé-Allainmat, Monique
-
supporting information
p. 318 - 327
(2015/12/30)
-
- Amine Catalysis for the Organocatalytic Diboration of Challenging Alkenes
-
The generation of in situ sp2–sp3diboron adducts has revolutionised the synthesis of organoboranes. Organocatalytic diboration reactions have represented a milestone in terms of unpredictable reactivity of these adducts. However, current methodologies have limitations in terms of substrate scope, selectivity and functional group tolerance. Here a new methodology based on the use of simple amines as catalyst is reported. This methodology provides a completely selective transformation overcoming current substrate scope and functional/protecting group limitations. Mechanistic studies have been included in this report.
- Farre, Albert,Soares, Kaline,Briggs, Rachel A.,Balanta, Angelica,Benoit, David M.,Bonet, Amadeu
-
supporting information
p. 17552 - 17556
(2016/11/28)
-
- cis-Semihydrogenation of alkynes with amine borane complexes catalyzed by gold nanoparticles under mild conditions
-
Supported gold nanoparticles catalyze the semihydrogenation of alkynes to alkenes with ammonia borane or amine borane complexes in excellent yields and under mild conditions. Internal alkynes provide cis-alkenes, making this protocol an attractive alternative of the classical Lindlar's hydrogenation.
- Vasilikogiannaki, Eleni,Titilas, Ioannis,Vassilikogiannakis, Georgios,Stratakis, Manolis
-
supporting information
p. 2384 - 2387
(2015/02/05)
-
- One-step Synthesis of Core-Gold/Shell-Ceria Nanomaterial and Its Catalysis for Highly Selective Semihydrogenation of Alkynes
-
We report a facile synthesis of new core-Au/shell-CeO2 nanoparticles (Au@CeO2) using a redox-coprecipitation method, where the Au nanoparticles and the nanoporous shell of CeO2 are simultaneously formed in one step. The Au@CeO2 catalyst enables the highly selective semihydrogenation of various alkynes at ambient temperature under additive-free conditions. The core-shell structure plays a crucial role in providing the excellent selectivity for alkenes through the selective dissociation of H2 in a heterolytic manner by maximizing interfacial sites between the core-Au and the shell-CeO2.
- Mitsudome, Takato,Yamamoto, Masaaki,Maeno, Zen,Mizugaki, Tomoo,Jitsukawa, Koichiro,Kaneda, Kiyotomi
-
supporting information
p. 13452 - 13455
(2015/11/10)
-
- Catalytic Semireduction of Internal Alkynes with All-Metal Aromatic Complexes
-
A simple catalytic method involving all-metal aromatic frameworks as precatalysts ensures an efficient route to (Z)-alkenes. Aromatic triangular palladium clusters were used to reduce internal alkynes without any trace of the formation of alkane side products. These trinuclear complexes provide a catalytic system that parallels the activity and selectivity of their best mononuclear peers, and the catalyst likely operates through complementary mechanisms.
- Deyris, Pierre-Alexandre,Ca?eque, Tatiana,Wang, Yanlan,Retailleau, Pascal,Bigi, Franca,Maggi, Raimondo,Maestri, Giovanni,Malacria, Max
-
p. 3266 - 3269
(2015/10/28)
-
- A concise stereoselective total synthesis of diplodialide C
-
An asymmetric total synthesis of diplodialide C has been achieved starting from commercially available homoallylic alcohol. Regioselective opening of the chiral epoxide, cross-metathesis reaction, and Yamaguchi macrolactonization were used as the key step
- Pratapareddy, Bommareddy,Sreenivasulu, Reddymasu,Hatti, Islavathu,Venkata Basaveswara Rao, Mandava,Raju, Rudraraju Ramesh
-
p. 1921 - 1926
(2015/10/29)
-
- Synthesis of Novel C-Pivot Lariat 18-Crown-6 Ethers and Their Efficient Purification
-
The syntheses of various lariat ethers including several not previously reported and their efficient purification are presented. The synthesis route brings together reactions from a variety of previous works leading to a robust and generalized approach to these C-pivot lariats. The main steps are condensation of functionalized diols with pentaethylene glycol ditosylate in the presence of potassium as a templating cation. Purification of the final products was achieved without chromatography by extracting from an aqueous potassium hydroxide solution.
- Jana, Susovan,Suresh, Vallabh,Lepore, Salvatore D.
-
p. 1977 - 1980
(2015/09/01)
-
- Tandem ring-closing metathesis/transfer hydrogenation: Practical chemoselective hydrogenation of alkenes
-
An operationally simple chemoselective transfer hydrogenation of alkenes using ruthenium metathesis catalysts is presented. Of great practicality, the transfer hydrogenation reagents can be added directly to a metathesis reaction and effect hydrogenation of the product alkene in a single pot at ambient temperature without the need to seal the vessel to prevent hydrogen gas escape. The reduction is applicable to a range of alkenes and can be performed in the presence of aryl halides and benzyl groups, a notable weakness of Pd-catalyzed hydrogenations. Scope and mechanistic considerations are presented.
- Connolly, Timothy,Wang, Zhongyu,Walker, Michael A.,McDonald, Ivar M.,Peese, Kevin M.
-
supporting information
p. 4444 - 4447
(2015/01/09)
-
- First stereoselective total synthesis of Neocosmosin A: A facile approach
-
First stereoselective concise synthesis of Neocosmosin A, with in vitro binding affinity for human opioid and cannabinoid receptors, has been reported using readily available starting materials such as methylacetoacetate, cyclohexanone, and homoallyl alco
- Dachavaram, Soma Shekar,Kalyankar, Kondbarao Balasaheb,Das, Saibal
-
supporting information
p. 5629 - 5631
(2014/12/11)
-
- TRICYCLIC BORON COMPOUNDS FOR ANTIMICROBIAL THERAPY
-
Provided herein are antimicrobial tricyclic boron compounds of the following formula I: or pharmaceutically acceptable salts, complexes, or tautomers thereof that are antibacterial agents, pharmaceutical compositions containing them, methods for their use
- -
-
Paragraph 0130; 0131
(2013/07/05)
-
- Development of a palladium on boron nitride catalyst and its application to the semihydrogenation of alkynes
-
The simple preparative method for a novel palladium supported on boron nitride catalyst (Pd/BN) was accomplished. Pd/BN is widely applicable for the semihydrogenation of mono- as well as disubstituted alkynes to furnish the corresponding alkenes in the presence of diethylenetriamine (DETA), which exhibits both an unprecedented acceleration effect toward the semihydrogenation and a suppression effect with regard to the overhydrogenation to alkanes. Copyright
- Yabe, Yuki,Yamada, Tsuyoshi,Nagata, Saori,Sawama, Yoshinari,Monguchi, Yasunari,Sajiki, Hironao
-
supporting information; experimental part
p. 1264 - 1268
(2012/06/15)
-
- Total synthesis of (+)-anamarine
-
Total synthesis of (+)-anamarine a polyoxygenated δ-pyranone natural product was accomplished via cross-metathesis protocol starting from 3-butene-1-ol and glycidol. Other key features of this synthetic strategy include use of Sharpless asymmetric epoxida
- Kumar, Krishnammagari Suresh,Reddy, Cirandur Suresh
-
experimental part
p. 2647 - 2655
(2012/04/23)
-
- Intermolecular mizoroki-heck reaction of aliphatic olefins with high selectivity for substitution at the internal position
-
New ligand for old reaction: The title reaction of aryltriflates with aliphatic olefins leads to substitution at the internal position with high selectivity. The ratio of the desired isomer (shown in the scheme) to the sum of all other isomers is generall
- Qin, Liena,Ren, Xinfeng,Lu, Yunpeng,Li, Yongxin,Zhou, Jianrong
-
supporting information; experimental part
p. 5915 - 5919
(2012/07/30)
-
- Catalytic enantioselective allylic amination of unactivated terminal olefins via an Ene reaction/[2,3]-rearrangement
-
The enantioselective allylic amination of unactivated terminal olefins represents a direct and attractive strategy for the synthesis of enantioenriched amines. We have developed the first use of a nitrogen-containing reagent and a chiral palladium catalyst to convert unfunctionalized olefins into enantioenriched allylic amines via an ene reaction/[2,3]-rearrangement.
- Bao, Hongli,Tambar, Uttam K.
-
supporting information
p. 18495 - 18498
(2013/01/15)
-
- Direct stereospecific amination of alkyl and aryl pinacol boronates
-
The direct amination of alkyl and aryl pinacol boronates is accomplished with lithiated methoxyamine. This reaction directly provides aliphatic and aromatic amines, stereospecifically, and without preactivation of the boronate substrate.
- Mlynarski, Scott N.,Karns, Alexander S.,Morken, James P.
-
supporting information
p. 16449 - 16451,3
(2020/09/15)
-
- Catalytic hydroacylation as an approach to homoaldol products
-
A method has been developed for the intermolecular hydroacylation of homoallyl alcohols with salicylaldehydes to furnish homoaldol products in 50-98% yields. The method also applies to the hydroacylation of 2-hydroxystyrenes. This work highlights the use of hydroacylation as a unified approach to both aldol and homoaldol products.
- Murphy, Stephen K.,Petrone, David A.,Coulter, Matthew M.,Dong, Vy M.
-
supporting information; experimental part
p. 6216 - 6219
(2012/01/06)
-
- Lewis acid-promoted addition of 1,3-bis(silyl)propenes to aldehydes: A route to 1,3-dienes
-
The Lewis acid-promoted addition of 1,3-bis(silyl)-propenes to aldehydes to provide the corresponding (E)-1,3-dienes in excellent stereoselectivity and good to excellent yields is reported. The procedure is mild, base-free, and operationally straightforward.
- Borg, Tessie,Tuzina, Pavel,Somfai, Peter
-
experimental part
p. 8070 - 8075
(2011/11/28)
-
- A concise stereoselective total synthesis of Botryolide B
-
The first total synthesis of Botryolide B is described from easily accessible starting materials. The synthetic strategy involves Jacobsen resolution, Sharpless epoxidation, Swern oxidation, Yamaguchi reaction, and ring closing metathesis (RCM).
- Reddy, B. Chennakesava,Meshram
-
scheme or table
p. 4020 - 4022
(2010/08/07)
-
- Synthesis of α-methyl ketones by a selective, iridium-catalyzed cyclopropanol ring-opening reaction
-
A mild method for synthesizing α-methyl ketones from substituted cyclopropanols is reported. This process, catalyzed by [CpIrCl2] 2, cleaves cyclopropanol rings regioselectively and more efficiently than the other conditions examined. While tertiary cyclopropanols afford α-methyl ketones, secondary cyclopropanols and cyclopropyl silyl ethers are less reactive and yield other isomerization products.
- Ziegler, Daniel T.,Steffens, Andrew M.,Funk, Timothy W.
-
supporting information; experimental part
p. 6726 - 6729
(2011/02/25)
-
- Short diastereoselective synthesis of the C1-C13 (AB Spiroacetal) and C17-C28 fragments (CD spiroacetal) of spongistatin 1 and 2 through double chain-elongation reactions
-
A unique and practical synthetic sequence for rapid access to polyketides and to further the spiroacetals derived from them, which utilizes a bidirectional Hosomi-Sakurai allylation approach around key allylsilanes in the synthesis of the AB and CD ring s
- Flowers, Christopher L.,Vogel, Pierre
-
scheme or table
p. 14074 - 14082
(2011/02/23)
-
- Total synthesis and assignment of the side chain stereochemistry of LI-F04a: An antimicrobial cyclic depsipeptide
-
(Equation Presented). The total synthesis of the potent antifungal and antibiotic cyclic depsipeptide LI-F04a and its side chain epimer was accomplished using macrolactonization to assemble the cyclic peptide core, followed by attachment of the 15-guanidino-3-hydroxypentadecanoyl (GHPD) side chain. The side chain was assembled by Yamaguchi-Hirao alkylation of both enantiomers of a chiral epoxide to provide a pair of enantiomeric side chains. The attachment of both these chains to the cyclic peptide allowed the absolute configuration of the side chain hydroxyl group in LI-F04a to be assigned as (R).
- Cochrane, James R.,McErlean, Christopher S. P.,Jolliffe, Katrina A.
-
supporting information; experimental part
p. 3394 - 3397
(2010/11/05)
-
- PYRAZOLE COMPOUNDS
-
The present invention relates to wherein each symbol is as defined in the specification. The compound has a superior mineralocorticoid receptor antagonistic action and is useful as an agent for the prophylaxis or treatment of a disease or condition mediated by the mineralocorticoid receptor activation.
- -
-
Page/Page column 71
(2010/04/30)
-
- Mechanistic investigation of the Candida albicans CCT 0776 stereoinversion system and application to obtain enantiopure secondary alcohols
-
Phenylethanol deracemization with Candida albicans CCT 0776 whole cells yields the (R)-enantiomer in over 99% enantiomeric excess and 98% yield. The deracemization process involves, in the first step, a fast, highly (S)-selective oxidation (NADP and O2 dependent) and, in the second step, a slower partially (S)-selective reduction (NADH dependent) of the intermediate ketone. The process was extended to other 2-alkanols, 1,2-diols and 1,3-diols and, with the exception of 1,3-diol (unreactive), the enantiomeric excess and yield of the deracemization were about 99% and 62-98%, respectively.
- Mantovani, Simone M.,Angolini, Celio F.F.,Marsaioli, Anita J.
-
experimental part
p. 2635 - 2638
(2010/03/30)
-
- A stereospecific palladium-catalyzed route to monoalkyl diazenes for mild allylic reduction
-
(Chemical Equation Presented) One step beyond: The first single-step stereospecific transition-metal-catalyzed conversion of allylic electrophiles into monoalkyl diazenes is described. This synthesis of allylic monoalkyl diazenes offers a new strategy for asymmetric synthesis by the reduction of optically active substrates or the use of chiral catalyst systems. Sensitive substrates are reduced in a highly selective manner. Ar = 2-NO2C 6H2.
- Movassaghi, Mohammad,Ahmad, Omar K.
-
supporting information; experimental part
p. 8909 - 8912
(2009/05/26)
-
- Hydroindation of allenes and its application to radical cyclization
-
Hydroindation of allenes and radical cyclization of 1,2,7-trienes (allenenes) were accomplished by HInCl2 with high regioselectivity to afford a variety of cyclic compounds. The resulting vinylic indiums could be used for successive coupling reactions in a one-pot procedure. The use of HInCl2 generated slowly in situ is extremely effective for the radical cyclization. The Royal Society of Chemistry.
- Hayashi, Naoki,Hirokawa, Yusuke,Shibata, Ikuya,Yasuda, Makoto,Baba, Akio
-
supporting information; experimental part
p. 1949 - 1954
(2009/01/31)
-
- Partial hydrogenation of alkynes to cis-olefins by using a novel Pd 0-polyethyleneimine catalyst
-
The creation and application of a new Pd0-polyethyleneimine complex catalyst (Pd0-PEI) was investigated. The 55 Pd 0-PEI catalyst was prepared by introduction of Pd(OAc)2 directly in the MeOH solution of deaerated PEI under Ar atmosphere. Reactions were carried out using 10 weight % versus substrate of 5% Pd0-PEI in 2mL solvent under H2 atmosphere at room temperature. The generality of the process was shown by disubstituting alkynes. Even for the substrate bearing a conjugated ketone on the alkyne, the serious over-reduction was not observed while significant cistrans isomerization of methyl styryl ketone accompanied the partial hydrogenation on the basis of keto-enol tautomerism. Pd0-PEI catalyst is also applicable to the partial hydrogenation of monosubstituted alkynes to monosubstituted olefins.
- Sajiki, Hironao,Mori, Shigeki,Ohkubo, Tomoyuki,Ikawa, Takashi,Kume, Akira,Maegawa, Tomohiro,Monguchi, Yasunari
-
supporting information; experimental part
p. 5109 - 5111
(2009/05/07)
-
- The first stereoselective and the total synthesis of Leiocarpin C and total synthesis of (+)-Goniodiol
-
The synthesis of the styryl lactone Leiocarpin C has been achieved in a highly stereoselective manner using Jacobsen's kinetic resolution, Sharpless asymmetric epoxidation and Sharpless asymmetric dihydroxylation as key steps. This is the first total synthesis of Leiocarpin C, and thus establishes for the first time the absolute stereochemistry of this natural product.
- Yadav,Premalatha,Harshavardhan,Subba Reddy
-
scheme or table
p. 6765 - 6767
(2009/04/11)
-
- Encapsulated molecular catalysts in polysiloxane gels: Ruthenium cluster-catalyzed isomerization of alkenes
-
Novel ruthenium-encapsulating polysiloxane gels are prepared by treatment of polymethylhydrosiloxane with diols in the presence of (μ3, η2,η3,η5-acenaphthylene)Ru 3(CO)7, and act as reusable catalysts in the isomerization of alkenes without leakage of the catalyst species. The Royal Society of Chemistry.
- Motoyama, Yukihiro,Abe, Motonori,Kamo, Kazuyuki,Kosako, Yusuke,Nagashima, Hideo
-
supporting information; experimental part
p. 5321 - 5323
(2009/03/11)
-
- N-isopropylidene-N′-2-nitrobenzenesulfonyl hydrazine, a reagent for reduction of alcohols via the corresponding monoalkyl diazenes
-
The reagent N-isopropylidene-N′-2-nitrobenzenesulfonyl hydrazine (IPNBSH) is used in the reduction of alcohols via the loss of dinitrogen from transiently formed monoalkyl diazene intermediates accessed by sequential Mitsunobu displacement, hydrolysis, and fragmentation under mild reaction conditions.
- Movassaghi, Mohammad,Ahmad, Omar K.
-
p. 1838 - 1841
(2007/10/03)
-
- An efficient, highly enantioenriched route to L-carnitine and α-lipoic acid via hydrolytic kinetic resolution
-
A general and practical approach for the synthesis of C-4 chiral building blocks using Jacobsen's hydrolytic kinetic resolution technique to resolve terminal epoxides and diols in high enantiomeric excess and excellent yields is described. The utilization of these building blocks for the synthesis of biologically important natural products L-carnitine and α-lipoic acid is illustrated. Georg Thieme Verlag Stuttgart.
- Bose, D. Subhas,Fatima, Liyakat,Rajender, Salla
-
p. 1863 - 1867
(2008/01/27)
-
- Synthesis of a potent hNK-1 receptor antagonist via an SN2 reaction of an enantiomerically pure α-alkoxy sulfonate
-
(Chemical Equation Presented) The concise synthesis of a stereochemically rich hNK-1 receptor antagonist is described. The synthesis is highlighted by an SN2 reaction of an enantiomerically pure α-alkoxy sulfonate (orthogonally protected butane triol), which was prepared by utilizing salen-mediated hydrolytic kinetic resolution technology. A stereocontrolled acetalization was employed to connect two enantiomerically pure fragments with a high degree of diastereoselectivity.
- Nelson, Todd D.,Rosen, Jonathan D.,Smitrovich, Jacqueline H.,Payack, Joseph,Craig, Bridgette,Matty, Louis,Huffman, Mark A.,McNamara, James
-
-
- Metal-catalyzed rearrangement of homoallylic ethers to silylmethyl allylic silanes in the presence of a di-tert-butylsilylene source
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(Chemical Equation Presented) In examining the scope of the di-rert-butylsilylene transfer to gem-disubstituted alkenes to form silacyclopropanes, we discovered an unprecedented reaction of homoallylic ethers. When silylene transfer was performed at room
- Cleary, Pamela A.,Woerpel
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p. 5531 - 5533
(2007/10/03)
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- Titanium-mediated carboxylation of alkynes with carbon dioxide
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The regioselective carboxylation of nonactivated internal alkynes can be performed with carbon dioxide under atmospheric pressure using a simple procedure based on the chemistry of Sato-type diisopropyloxytitanacyclopropenes. Various polysubstituted vinylcarboxylic acids and butenolides can be prepared in this way. In addition, this paper describes an experimental protocol for the preparation of solutions of (η2-cyclopentene)diisopropyloxytitanium. This complex also reacts with carbon dioxide, and mediates pinacol coupling of acetophenone. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
- Six, Yvan
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p. 1157 - 1171
(2007/10/03)
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- Metal-catalyzed silacyclopropanation of mono- and disubstituted alkenes
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As an alternative to the strongly reducing conditions necessary for the formation of silacyclopropanes, silylene transfer was developed as a mild, functional group tolerant method of silacyclopropanation. Complex silacyclopropanes were formed from functio
- Cirakovic, Jelena,Driver, Tom G.,Woerpel
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p. 9370 - 9371
(2007/10/03)
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- Stereoselective, oxidative C-C bond coupling of naphthopyran induced by DDQ: Stereocontrolled total synthesis of deoxyfrenolicin
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(matrix presented). A formal total synthesis of pyranonaphthoquinone natural product deoxyfrenolicin 1 is described. The key step in the synthesis involves the use of stereoselective 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)-induced C-C bond couplin
- Xu, Yao-Chang,Kohlman, Dan T.,Liang, Sidney X.,Erikkson, Chad
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p. 1599 - 1602
(2008/02/10)
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